Evolution / Genetics

Ancient clay tablets are being used to track down lost Bronze Age cities in Turkey. A stockpile of 12,000 trade accounts left by Assyrian merchants in the 19th Century BC has been used to find half a dozen locations.

A clay tablet with cuneiform inscription from Anatolia circa 1875-1840 B.C. Researchers have extracted numbers from thousands of these tablets to create a database of trade in ancient Assyria [Credit: Los Angeles County Museum of Art]

The researchers used mathematical models based on the prices of goods and the frequency of trips between trade hubs to pinpoint where the cities once stood.

Some of the coordinates, calculated by a team led by Harvard University researchers, place Assyrian cities hundreds of miles from previous estimates.

But the economists warn that officials are unlikely to organise excavations based on their findings as 'the world of archaeology is a world of international politics'.

The traders, whose homeland lay in what is now Iraq, carved the tablets after settling in Turkey around 4,000 years ago.

Here they swapped tin and fabric transported from their homeland for silver and gold from the local kingdoms.

The merchants formed part of the Old Assyrian trade network, which connected northern Iraq, Northern Syria and central Turkey during the Middle Bronze Age period from 2000-1650 BC.

It is one of the earliest well-documented long-distance trade networks in world history.

Excavations of the ancient city of Kanes, whose ruins were found near the modern Turkish city of Kayseri (Caesareia) during the 20th Century, have uncovered numerous contracts, shipment manifests and detailed business letters carved into clay tablets.

Ancient clay tablets are being used to track down lost Bronze Age cities in Turkey. Experts used mathematical models based on the prices of goods and the frequency of trips between trade hubs to pinpoint where the cities once stood (newly placed hubs highlighted in white) [Credit: Daily Mail]

Much of the texts' contents is trivial by historians' standards, with merchants writing of deals involving donkeys, as well as begging letters from sons to their fathers.

'I met with the king in Ninassa, but . . . he did not buy a single textile,' one trader wrote.

But the volume of transactions written into the tablets has allowed researchers to map the location and size of several ancient Assyrian cities.

The Assyrian records mention the city of Sinahuttum 14 times as the home of a 'market for donkeys' and a popular wool exchange.

The trade model created by the researchers places it northeast of Hattusa, near modern Bogazkale.

The locations of nine other ancient Assyrian hubs have been tracked down using the model, including Durhumit, Kuburnat, Suppiluliya and Washaniya.

The technique used by the team involved a 'structural gravity' model and is based on methods used by modern economists.

It took information from the tablets, such as the price of goods in each city, the estimated distance between them and cost and most frequent purpose of travel.

This information was then used to make guesses on where the coordinates for each city might lie.

The researchers say their 'quantitative' method gives them more accurate locations than historians' 'qualitative' methods of analysis using descriptions in ancient texts.

In some cases the team's estimates put the cities in similar spots to the estimates of historians, while in others the sites are found to be hundreds of miles away.

Professor Ali Hortacsu, an economist at the University of Chicago and one of the paper's authors, said mapping trade networks could help experts understand how prosperous each city was.

Study lead author Gojko Barjamovic, of Harvard University, said Turkish officials are unlikely to authorise excavations on the basis of the research.

'The world of archaeology is a world of international politics and cultural heritage preservation,' he added.